Electric switch



A. C. GAYNCR ELECTRIC SWITCH Nov. 1, 1932.

2 SheetsSheet 1 Filed NOV. 25, 1950 INVENTOR. CBdM ORNEY A. C. GAYNOR ELECTRIC SWITCH Nov. 1, 1932.

2 Sheets-Sheet 2 Filed Nov. 25, 1930 [Ill TORNEY Patented Nov. 1, 1932 TTES PATENT GFFECE ARTHUR G. GAYN'OPJ, OF STRATFOED, CONNECTICUT ELECTRIC SWITCH Application filed November 25, 1930,

pers for example, the tool should be under the control of the operator so long as the motor is being driven, otherwise the tool or appliance may get out of control and cause considerable damage to be done to the work,

a floor, for instance, or adjacent objects such as the walls, fixtures or the like. The workmen are instructed in this regard, yet it has frequently occurred that the operator, in stead of throwing off a switch carried by tool, pulled out the attachment plug at the end of the table supplying current to the tool to stop the motor, and subsequently reinserted the attachment plug without holding the tool with the result that the motor would drive the tool and cause the damage stated.

An object of this invention is to provide a switch and tool handle mechanism which is so organized that the moment the operators grip is released, the switch is turned off, thus stopping the motor, and requiring the presence of the operators hand upon the tool to start the motor. In the specific form of this invention illustrated herein, this is accomplished by providing a rotating handle on the tool and con nee-ting this handle to the switch mechanism,

the spring of which normally tends to move the handle in one direction, that is in 05 direction. In this arrangement to throw the switch on, the handle must be turned by he operator and the moment that the grip is releasedthe handle and switch mechanism will cause the switch to be thrown oil.

A particularly important and advantagoon feature of this invention is the arrangement of the parts so that while full movement of the handle is required to throw the switch on, the extentof the ordinary movements of the handle incident to the manipulation of the tool by the workman will not throw the switch .ofl, but it will only be thrown ofi? when the grip on the handle is completely released. Thus, the operator may use the tool without being constantly mind- Serial No. 498,064.

ful of the position of the handle or the switch mechanism so long as the grip on the handle is maintained, and, as stated above, the motor will be rendered inoperative immediately upon the release of the operators grip on the handle.

4 ther features and advantages will here inatter appear.

In the accompanying drawings illustrating one form of my invention, that at present preferred Figure 1 is a top plan view of the handle portion of the floor scraper showing the switch mechanism of the present invention applied thereto, the cover plate for the casing for the switch being broken away to show underlying parts.

Fig. 2 is a longitudinal sectional view through the switch proper showing the means for normally urging the switch to circuit opening position and the yoke for supporting the switch.

Fig. 3 is a longitudinal sectional view taken through the tool handle and switch actuating mechanism and showing the latter in oil position, that is in position where the operators hand is not gripping the handle.

Fig. l is a similar View showing the actuating mechanism in the position to which it is moved to throw the switch on.

(J Fig. 0 IS a similar view which shows by comparison with Fig. l the amount of oscillation which the hand grip may have before the switch has moved sufiiciently to cause it to open the motor circuit. 7

The tool handle shown in the accompanydrawings by way of example is attached to a rod or pipe 10, the other end of which is connected to a motor driven machine such, for instance, as a floor scraper. It has a neck 11 threaded to receive therod or pipe 10 and a housing 12 for the switch. At the side opposite the neck 11, the switch housing 12 has a pair of arms 13 in which there is supported a hand grip 14:. This hand grip 1a is usualy rotatably mounted on a rod 15 so that the movements of theoperators hand in the vertical plane while encircling the grip 14: may occur without chafing the operators hand. The tool is propelled foriou wardly and backwardly by force exerted by the operators hand engaging the grip 14 and it is kept from swinging and is-steered by a'bar 16 extended at right angles from.

thepipe l and having a hand grip 17 on its extremity. Inusing the tool, the hand engagingth e' grip 17 does :mostiojf the work while the hand engaging the grip l,

disastrous results However, should both hands be released from the grips 14 and. 17 while the motor driven tool is operated, the

I scrapers r or other employed would 'ofier such resistancethatthe motor ineiiect A would turn the machine rather -thafi-turn the s 'erapei s with the result that the handle and pipe might be thrown about promiscuous 1y, damaging adjacent walls,furniturearid v iixt'uresiif not actually doing bodily injury.

to the workmen or other persons in the i'q' ity f Her-etofore, a "maii'usilly operated snap switch or the like was provided in the housing 12 to be manipulatedby the operator to close and openthe circuit to the niotoriwh'en starting and stopping the use of the tool.

' Workingsu's'ing the'tool are instr ucted.to

throw the switch of? wh n finishin workmen liav e from time to time merely titles thej' liig is; ettabhed'to came 19 and entering the housing flil throughanop'en 111 20. 1 it l wer porti n, ut of h me?- ta cle from which current s being supplied to the qjo -f Th s Q fc i-ii ise;we b dose Y fore both hands were taken from the tool and thus he g ccident wens occur during disconnection Qf'llllg too'l from the sourceof "current; How ever, whenm'ovlng the tool;

to anotherfpart of the roo ii to beginwork at'that place {not infrequently a workman would insert the/attachment plug 18'i'nto the QpOSsible iiry as aboi est ejted'.

receptacle without .first taking hold 9f t e lmndl oi? th @0 1 d ce a "$9011 as the motorstarted the handle and pipe '10 would spin aroiiiid and causeljdama'ge' and I Such improper and-dangerous performance of .thework has been avoidedyby the,"

; .7 6- 1 l .-w v present "invent on prov ding means on thehandlei or moying the switch-to circuit clos ng pos tion and automat c means ferife L turninggthe sw tch to open-c1rcu1t position en :the; loperators grip on the tool is rel ase .H e fb e s it h. me en hav e Pr vided wher s, in i l y hanidle mu be maintained gripped toward "the z'main theop'erator to keep lithe circuit 'Q Q B L b t 's sh'dev l ss 'q 'lhs, n w r to 'm'air'itain them operated',"qu1cklf, tire the wire by the workman, very pnrp ose.

pose defeatedby the means available, to the 'o'rclinar-y workma'n.

In the drawingsillustratin myinvention, I

finger and hand muscles of the operator and thus unduly fatigue the workman. Besides this,-and due to the fatigue produced bynits, f; use, such auxiliary grips may beand hav'e 7 on occasion been tied down by a cord or thus defeating their 1 I haveshown-the switehesfa' sn'ap' switch ee I Fig. 2,ihavi ng iabase 2l and: cap 22 held I togetlrer and' attached to a "yoke 23 by screws '2e,;the yoke-23 a-v ng hor zontal lugs V resting en-shoulders-26in;theswitchhousinglQ-andheld in place by screws 27 threaded;

'infthe housing 12=which also serve toihold the i i i coverf'plate 28 inoperativeposition.

- The switch comprises oppositely disposed v contacts 29, one pair oiiwhich is connected f to wires30supplying ciirrent to the device my copending applicationserial No.1 452,545,

filed May.1 5,'1930. The switch isfnormally" biased so that a Switchblade '32 shown in dotted *lines iii'Fig; 2;is dis-engaged if'romf the contacts 29 keep the circuit opjeii l This switch blade, which may beef the type dis closed inmy Reissue Patent No. 18,' 385,'da ted,- 1' March 15,'193 2, i s mounted on a crank 33 fulcrumed in a-{irame 34yand supporting the-LE lower endof a spring35'. The upperendof the spring is en agedby an actuatingarm 36 i and'the other "pair of which iscojnnected wires31leadingtothem'oton Thesecontactsi i maybe of the-type disclosed *andflclaiined in thetool, but in-spiteof these instrn ions. throughthoughtlessness or otherwise, the

carried by a h nd i rtime-t1 ates: l The mechanism-f0r throwing the switch blade from jo'ne to another position is more com pletely-descrlbed,and'may bejof thetypedisi closed; in my-fPa-tent No.]1-,852 ,772, dated April 5, 1932, Inthe noimal'h 'and operation of a switch 'ofthiskind, itis throwi1"on:an'd eoijt by manipulating the 'handleg37 whibhj causes"theactuator 36 to carrythe spring 35 across the a Xis of 'os'cilletion of thecrank 33 sothat the lower endof the-spring will throw 1 the cram; to 'thenw-=position'-. This handle 'I maybe of-thety'pe" disclosed in copendingflf application serial 0'. 276,886,1i1ed May/11,;

1,928. In agswitchof this kind, considerable movementjofthehandle 37 may ble'efi'ectedb'e or fore the sprin is careied across the axislof oscillation "of the crank and thisc harecteris a. tic of snap switches isE'taken advantage of to jfurltherau'grr'fent the freedom ofmoyjem'ent of 1 f 7 the tool grip-which controls the switch withajs win-menses sp en The actuator 36 and handle 37 are normally urged to circuit-opening position, that shown in Fig. 2, by a spring 39 having a ball 40 resting in a recess 41 in the handle, similar to the mechanism disclosed in my copending application Serial No. 403,437, filed October 30, 1929. For the sole purpose of actuating the switch, the spring 39 may be slightly more powerful than the spring 35. However, since the spring 39, according to the present invention, has other functions, it is made more powerful than it would need to be solely to actuate the switch. The handle 37 of the switch comprisesa bar constituting in effect a first-class lever with the arms 42 and 43 thereof horizontal and as shown in these arms 42 and 43 are angularly disposed so that one of the arms protrudes upwardly while the other is parallel to the base 21.

To actuate this switch so that the blade 32 moves into engagement with the contacts 29 and so that this may be done without fatiguing the operator, there is provided by the present invention a bar 44 extending substantially parallel with the pipe 10 and having at one end a pin 45 extending into a hole 46 in the housing 12 by means of which it is fulcrumed. This bar 44 overlies the arm 43 of the switch handle 37 and extends out of the housing 12 through an opening 47 and from that point extends to the hand grip 14.

It may do this in any suitable way. As shown, the bar 44 is provided with a cross piece 48 having rearwardly extending arms 49 lying within and quite close to the arms 13 which carry the grip 14. At their rear ends the arms 49 extend into apertures 50 at the ends of the hand grip 14. These arms 49 and apertures 50 are so shaped that when the hand grip 14 is disengaged by the operators hand the spring 39 in the switch raises the end 43 of the handle 37 and this lifts the bar 44 so that the extreme ends 51 of the arms 49 rotate the hand grip 14.

lVhen the workman desires to use the machine, the hand grip is grasped at a point lower than would be customary and as the hand is raised the grip 14 is turned so that the walls 52 of the apertures 50 cam the arms 49 downwardly to the position shown in Fig. 4, during which operation the bar 44 depresses the arm 43 of the switch and shifts the spring 35 causing the blade 32 to close the motor circuit through the wires 31. This operation was of course performed against the tension of the springs 35 and 39. However, once the spring 35 has been moved over the axis of oscillation of the crank, it does not react with any tendencies to raise the bar 44 or turn the handle backwardly, that is clockwise as shown in Fig. 4.

Having thus started the motor, the operator proceeds to perform the work desired with the machine and in doing so he need not exercise any caution as to the extent of movement of the grip 14 which occurs due to the movements of his wrist in propelling the machine back and forth, for the handle may move, in the form of the invention herein disclosed, approximately 90 from the position shown in Fig. 4 to the position shown in Fig. 5 before the handle 37 of the switch has rocked far enough to carry the spring 35 across the axis of oscillation of the crank. This freedom of 90 of movement of the grip 14 has been found in practice suflicient to ac commodate all natural movements of the operators hand in manipulating the tool.

The spring 39 and the leverage of the bar 44 and arms 49 thereof, is such that practically no effort is required to rotate the grip 14 or to maintain it in any position to which it may be rotated. It will be seenrthat so long as the operators hand engages the grip 14 the switch will be kept on whether or not the operators fingers tightly hold the grip, and that as soon as the operators hand is removed from the grip 14, the spring 39 will rotate the-grip 14, return the bar 44, and cause the handle 37 of the switch to move to circuitopening position.

The ends 51 of the arms 49 and the ape-rtures 50 in the grip 14 are so related that the grip can neither be swung clockwise nor counterclockwise sufficiently to permit the ends 51 to completely disengage the apertures 50. Hence, in assembling the switch, the bar 44 is first inserted through the hole 47 in the housing 12, then the ends 51 0f the arms 49 are inserted in tne apertures 50 and finally the rod 15 on which the handle is fulcrumed is inserted through aligned aperturesin the arms 13 and the grip 14, the rod being held in place by ends 53.

Variations and modifications may be made within the scope of this invention and portions of the improvements may be used without others. H

Having thus described the invention, what is claimed as new and forwhich it is desired to obtain Letters-Patent, is

1. In combination with a tool handle, a hand-grip mounted for rotary movement; an electric switch; and means interconnecting the hand-grip and electric switch for actuation either one by the other.

2. In comhi ation with a tool handle, a hand-grip mounted for rotary movement; an electric switch normally biased to move in one direction; and means connecting the hand-grip to the electric switchfor operation of the latter by the former and for the return of the hand-grip to normal position by the switch when the hand-grip is released.

3. In combination with a tool handle, a hand-grip mounted for rotary movement; an electric switch having an actuating means and means for normally urging the actuating mechanism to circuit-opening position; and means interconnecting the hand-grip and actuating; mechanism of the switch for oper; spi e: of the latter by the former'when turned haiidto move the adtuating'inechanism to hand nieunted for rotaryniovement an ele ric; switchha'ving' an'actuating meansand means for normally'ui gingthe actuating mechanism "to circu t-opening posltion and means interfconnecting' the hand-grip and a'ctu'zi'tingj mechanism otthe switch for'op:

I ejra rshand "releases the hand-grip; I

- llin mbina tool-directinghand-grip mounted for turnhpvement within limits; and means inclndin' a snap switch actuatedflby the handat limits: of its turning movements to opena'nd 'cl osfe'acirCH'itOf the'tool. "6, In combination with artoolf handle,- a tool-directing hand grip' mounted for turning movement within limits; and means-ineluding a snap switchactuated by the -hand-, gripat-onelimit ofits turning movement to cl'osea circuit off-the tool. .7 g g V 7, Combination with a tool, handle, a tool-difecting handfgrip mounted for turning' movement within limits; and'ineans including av snap switch actuatedby the handgr'ipatjone limit of its turning mov'ement to close 'a c ino'uit of'the' tool, thelsnap switch re ma nin'gin circuit-closing position during substantiallythe entire return movementof theha-n'dle. I g Y a 8.1 Inoombination with a tool, handle,- a tool-directing hand-grip mounted for turning movement within limits; and means including a snap switch actuated by the handgrip at one limit of its turning movement to closea circuit: of the tool, the snap switch having'ai spring normally tending to move it to'circuit opening position and through said means normally tending to return the handle to initial position.

, 9 In combination with a tool handle, a hand-grip mounted for rotary movement; an

electric switch mounted on the; handle and having; an actuating, member"; and a bar ful- V cr-urnejd on vthe; handle, jengaging the actuat v ing'mei'nber,oftheswitch and connected to the hand;gr-ijpj to'be rocked by the .rotaiy mo'vementf thelajttei to operatethe actuat- 7 ing membeljyoii the s witeh.

10.- Incombinati'on with a 651 handle'hav- ,ing'a switc h housi'ng andspace'd arm-s extending outw'ardly'from-the switch ho sin 'a hand-grip mounted in the spaced arms for rotary movement an electric switch mounted membery and abanfulorurned; in the in the switch housing andhaving an actuat r p to initia'l" position when the opon with a tool handle, a

switch housing engaging the actnatingmembera of the switch .th'erein and extending out? wardlyfroin theihousing 'inathe direetion of i the forked arms, saidba'r being-connected to I the hand-grip fon'actuation therebyt l j 11. 'Incombination with a toolhandle havrotar'y movement ane'lectii'o switch mounted 111g switch housing'anfd spaced arm's; ex? if r tending outwardly fro nfthe'switchhousingyi ahaI C -gripmountedin the-spaced armsffof fi '75. inthe switch housing andhaving ana tuat-i J switch housing engagingthe actuating meme be'r oft-he, switchthe'reinnnd'extending out 1 i 7 e0 the forked arms; sai'd bai'f havi'ngan end en gaging a notch in; thehand-gripfof a tuaayhem the housing in thedirection oof ing a switch, housing and spaced {arms lex ing member; and a bar fulbrurned' inlthe" her of the switch therein} and extending out 9 wardlyfrom the housing;in tte-di eetiong-of 7' the forked arinsj, said barhaving arpair' of 9 I arms extendingdin'thejdirection of the spaced armson thehandle "and h'avingj thei1 ends i extending into notches in the handle so that; f the bar will be' depressed by rotation the handlef o I 13. In combinationl with a; tooloha'nd'lej a" in'g movement within limits a switch aetu atedby the handgrip atone limitof itsturn} ingmovement to clbseia-circuit of the tool; I:

105V 7 L tl'ie" switch permitting turning movementof theTh'andle -.inc1de'nta l to movementsI-ofjthe r operators hand in" manipulatingi'the tool and means interconnecting the handsgrip and without ca'usingtheswiteh'toopen the circuit of thetooL r tooLdireeting hand-grip mounted fonturnl 7 j 110 so 14Incombination with atoolha'nclle, a" hand grip mounted for turning movement 7 an electric switch-for controlling a circuit'; actuatingmeans for said switch; 'means in terconneeting the; hand-grip and actuating mechanism o fthe switchforfopeiation o'fth'e latter by theformenwhen the'grip isftli'rned said switch for normally urging' thef switchactu'atlng mechanism and theinterconnected Signdiat Stratfotd o'fNovemb'er', 1930;

RTH R i by hand to close the" cifcuit; andmeans 'in'ff I hand-gripitoward circuit ope'ningposition. 7' j I r ,si'ntheeountyfof Fair? field, andSta'te of Connecticut,this'24th day" i eo i '7 

